摘要
采用膨胀颗粒污泥床(EGSB)处理高浓度同时含有氨氮和硝酸盐的有机废水,重点探究碳氮比(COD/TN)对系统生物产气及脱氮除碳性能的影响.136d运行结果表明:C/N对系统COD去除影响不显著,而对产甲烷和TN去除率影响显著.分时水质测定证实了亚硝酸盐氮积累及硝酸盐短程还原与厌氧氨氧化(Anammox)耦合.C/N为5.71时产甲烷、硝酸盐短程还原耦合Anammox效果最好.随着C/N升高,厌氧氨氧化活性下降,而产甲烷和硝酸盐异化还原(DNRA)活性增强.C/N能够显著改变污泥胞外聚合物组分、含量及有机基团,进而影响污泥结构稳定性及微生物代谢活性.Anammox菌Candidatus Kuenenia和Candidatus Brocadia相对丰度低C/N时远高于高C/N,高C/N下检测到了大量产甲烷菌Methanothrix、Methanolinea和Methanobacterium,同时共存反硝化菌和DNRA菌.微生物功能基因注释证明了短程反硝化/DNRA促使亚硝酸盐积累和Anammox发生以及乙酸途径产甲烷.最后,提出了最佳C/N下碳氮同步去除机制.
An expanded granular sludge bed(EGSB)was used to treat high-strength organic wastewater containing both ammonia and nitrate.The effects of carbon to nitrogen ratio(COD/TN)on biogas production and nitrogen and carbon removal were mainly investigated.The 136-day operating results showed that C/N had no significant effect on COD removal,while significantly affected methanogenesis and TN removal efficiency.The time-course water quality determination confirmed nitrite accumulation and the coupling of nitrate partial reduction with anaerobic ammonia oxidation(Anammox).When C/N was 5.71,the coupling effect of Anammox with methanogenesis and nitrate partial reduction was optimal.With the rise of C/N,anammox activity decreased,while activities of methanogenesis and nitrate dissimilation reduction(DNRA)increased.C/N could significantly change the composition,content and organic groups of extracellular polymeric substance in sludge,and then affect the stability of sludge structure and microbial metabolic activity.The relative abundances of Candidatus Kuenenia and Candidatus Brocadia of Anammox bacteria were much higher at low C/N than those at high C/N.At high C/N,a large number of methanogens including Methanothrix,Methanolinea and Methanobacterium were detected,meanwhile,denitrifying and DNRA bacteria were co-existed.Microbial functional gene annotation proved that partial denitrification/DNRA promoted nitrite accumulation and thus Anammox occurrence,as well as methane production via acetic acid pathway.Finally,synchronous carbon and nitrogen removal mechanism was proposed at optimal C/N.
作者
周鑫
赵瑞强
韩晋
ZHOU Xin;ZHAO Rui-qiang;HAN Jing(College of Environmental Science and Engineering,Taiyuan University of Technology,Jinzhong 030600,China;Innovation Center for Postgraduate Education in Municipal Engineering of Shanxi,Jinzhong 030600,China)
出处
《中国环境科学》
EI
CAS
CSCD
北大核心
2024年第10期5445-5452,共8页
China Environmental Science
基金
国家自然科学基金项目(21607111)
山西省基础研究计划项目(20210302123198)
山西省专利转化计划资助项目(202401011)。
关键词
碳氮比
高浓度废水
产甲烷
厌氧氨氧化
硝酸盐异化还原
去除机制
C/N
high-concentration wastewater
methanogenesis
anaerobic ammonia oxidation
nitrate dissimilation reduction
removal mechanism
